From Mushin:

You may have noticed that we often encourage people who practice at Sangha Jewel Zen Center to take up a service position here as an aspect of a vital zen practice. Zazen is important, yes, but/and there’s more to this practice besides meditation. We emphasize that a complete spiritual path supports our ability to function in our life on behalf of the community, or communities, that we are part of. We all pitch in. This is where we express our relationship to all life.  We don’t just receive the fruits, we tend and offer the fruits as a fulfillment of this spiritual tradition.
I recently received a note from Bansho, who’s been training in Japan at Toshoji Monastery for three months. He mentions that when Docho Roshi (old teacher) at Toshoji was looking at some of the records of the temple, he came across a mention of Ryokan, the Zen poet-monk who lived from 1758-1831. When a memorial was being offered at Toshoji, Ryokan had served as the tea cup washer for that week-long service. Helping in various work positions has always been part of the Soto Zen training approach. It’s recognized as the expression of living as an awakened human being. There is no job too lowly for us to do, when needed. It’s an opportunity to remember that we are just ordinary beings, who have the good fortune to experience well-being that comes from living a life of service, in whatever field we are living.. . . anywhere, everywhere.